A dishwasher comprising a heat pump

ABSTRACT

The present invention relates to a dishwasher comprising a body; a heat pump that is disposed inside the body and that has a first heat exchanger providing the heating of the water to be used in the washing step, a second heat exchanger transferring the heat received from the first heat exchanger to the wash water and a compressor fluidly connected to the first heat exchanger and the second heat exchanger, realizing the refrigerant cycle; a water collection tank that is disposed just under the first heat exchanger, wherein the water condensing on the first heat exchanger is collected, and a water softening unit that enables the water taken from the mains to be softened so as to be used in the washing step.

The present invention relates to a dishwasher comprising a heat pump.

In heat pump dishwashers wherein closed cycle drying process is applied, the heat pump used for washing and drying the dishes is composed of heat exchangers named as evaporator and condenser. During the drying process and in cases wherein the condenser is operated to heat the wash water, hot and dry air is passed over the tub wherein the articles to be washed are placed. Humid air leaving the tub leaves its moisture while passing over the evaporator that works as the condenser and warms while passing over the condenser that works as the heater. The air that heats up with the removal of its moisture is sent into the tub throughout the drying cycle. The humid air condensing on the evaporator fins trickles down as water droplets due to the effect of the gravity and these droplets accumulate in the lower water collection chamber under the evaporator. However, the collected water, until it is discharged, humidifies the processing air and decreases the drying performance of the dishwasher and cause generation of undesired bad odors.

In the state of the art European Patent Application No. EP2682036, a dishwasher is disclosed, wherein the water condensed in the evaporator is directed into the washing tub in the washing step.

In another state of the art European Patent Application No. EP2682037, a dishwasher is disclosed, wherein the condensed water is discharged together with the wash water.

The aim of the present invention is the realization of a dishwasher with increased washing performance and decreased water consumption.

The dishwasher realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof, comprises a body; a heat pump that is disposed on the body and that has a first heat exchanger with heating function, a second heat exchanger transferring the heat received from the first heat exchanger to the wash water and a compressor connected to the first heat exchanger and the second heat exchanger and pressurizing the refrigerant fluid passing through the first heat exchanger and the second heat exchanger; a water collection tank that is disposed just under the first heat exchanger and that contacts the first heat exchanger, thus wherein the condensed water vapor is collected, and a water softening unit that enables the water received from the mains to be softened so as to be used in the washing step. During the water heating process, the ambient air is used as a heat source and the heat in the air is drawn by the heat pump. When the air used in the heating process hits the surface of the first heat exchanger, the water vapor in the air condenses and passes into the liquid phase with the effect of the temperature different between the air and the first heat exchanger and is collected in the water collection tank disposed under the first heat exchanger with the effect of gravity.

The dishwasher of the present invention comprises a sump that is connected to the water collection tank and the water softening unit; a pump that provides liquid transfer between the water collection tank and the water softening unit and the sump, and a control unit that realizes the process of transferring the water in the water collection tank into the sump and the water stored in the sump into the water softening unit in accordance with the predetermined algorithms. The control unit enables the water accumulated in the water collection tank after condensing on the first heat exchanger to be used in the water regeneration process. Thus, the water collected in the water collection tank is prevented from revaporizing and increasing the moisture in the body, and the amount of water taken from the mains for the regeneration process is decreased.

In an embodiment of the present invention, the sump is disposed above the water softening unit. Thus, the water accumulated in the sump is taken into the water softening unit with the effect of gravity without requiring operating the pump during the regeneration process with resin.

In an embodiment of the present invention, the dishwasher comprises a level sensor that measures the level of the water accumulated in the sump and in this embodiment, the control unit checks the signal received from the level sensor and operates the pump, thus providing the intake of the water from the sump into the water softening unit.

In an embodiment of the present invention, the control unit checks the water level received from the level sensor and enables the water to be delivered to the water softening unit to be taken from the mains when needed.

In an embodiment of the present invention, if the level of the water accumulated in the sump is below the water level predetermined by the producer, the control unit operates the heat pump independently from the washing and drying needs, enabling the amount of water accumulated in the sump to be increased. Thus, the amount of water sufficient for the regeneration process is enabled to be accumulated in the sump.

In an embodiment of the present invention, the dishwasher comprises a heater that is disposed in the vicinity of the sump. Thus, the heater enables the water stored in the sump to be heated and taken into the water softening unit, thus increasing the efficiency of the regeneration process.

The dishwasher realized in order to attain the aim of the present invention is illustrated in the attached figures, where:

FIG. 1—is the schematic view of a dishwasher.

The elements illustrated in the figures are numbered as follows:

-   1. Dishwasher -   2. Body -   3. First heat exchanger -   4. Second heat exchanger -   5. Compressor -   6. Heater -   7. Water collection tank -   8. Water softening unit -   9. Sump -   10. Pump -   11. Control unit -   12. Level sensor

The dishwasher (1) comprises a body (2); a heat pump that is disposed inside the body (2) and that has a first heat exchanger (3) providing the heating of the water to be used in the washing step, a second heat exchanger (4) transferring the heat received from the first heat exchanger (3) to the wash water and a compressor (5) fluidly connected to the first heat exchanger (3) and the second heat exchanger (4), realizing the refrigerant cycle; a water collection tank (7) that is disposed just under the first heat exchanger (3), wherein the water condensing on the first heat exchanger (3) is collected, and a water softening unit (8) that enables the water taken from the mains to be softened so as to be used in the washing step. For the regeneration of the resin that is disposed on the water softening unit (8) and that becomes saturated after more than one washing cycles, the water is transferred to the water softening unit (8) after the washing cycles predetermined by the producer.

The dishwasher (1) of the present invention comprises a sump (9) that is connected to the water collection tank (7) and the water softening unit (8); a pump (10) that is disposed between the water collection tank (7) and the water softening unit (8), and a control unit (10) that enables the water in the water collection tank (7) to be transferred to the sump (9) and/or the water stored in the sump (9) to the water softening unit (8) by means of the pump (10). The water condensed on the first heat exchanger (3) and accumulated in the water collection tank (7) is pumped into the sump (9) by means of the pump (10) and collected in the sump (9). The water stored in the sump (9) is controllably transferred to the water softening unit (8) after the washing cycles predetermined by the producer and used in the resin regeneration process. Thus, the water condensed on the first heat exchanger (3) is prevented from increasing the moisture in the dishwasher (1) while the water consumption of the dishwasher (1) is decreased.

In an embodiment of the present invention, the sump (9) is disposed in the vicinity of the water softening unit (8). Thus, the water stored in the sump (9) is transferred to the water softening unit (8) without increasing the energy consumption.

In an embodiment of the present invention, the dishwasher (1) comprises a level sensor (12) that measures the level of the water accumulated in the sump (9) and in this embodiment, if the value received from the level sensor (12) is above a water level value predetermined by the producer, the control unit (11) operates the pump (10), thus providing the intake of the water from the sump (9) into the water softening unit (8).

In an embodiment of the present invention, if the water level received from the level sensor (12) is below the water level value predetermined by the producer, the control unit (11) enables the water to be delivered to the water softening unit (8) to be taken from the mains. Thus, in case the water in the sump (9) is not sufficient, the regeneration process is enabled to be realized with the mains water.

In an embodiment of the present invention, if the water level received from the level sensor (12) is below the water level predetermined by the producer, the control unit (11) operates the heat pump independently from the washing and drying needs, enabling the amount of water accumulated in the sump (9) to be increased. Thus, the amount of water sufficient for the regeneration process is enabled to be accumulated in the sump.

In an embodiment of the present invention, the dishwasher (1) comprises a heater (6) around the sump (9) and the heater (6) enables the water stored in the sump (9) to be heated and to be taken into the water softening unit (8). Thus, the effectiveness of the regeneration process is increased.

By means of the present invention, in particular by using the water condensed on the first heat exchanger (3) and collected in the water collection tank (7) in the regeneration process, the condensed water is prevented from revaporizing and increasing the moisture in the body (2) and the amount of water taken from the mains for the regeneration process is decreased. 

1. A dishwasher comprising a body; a heat pump that is disposed inside the body and that has a first heat exchanger providing the heating of the water to be used in the washing step, a second heat exchanger transferring the heat received from the first heat exchanger to the wash water and a compressor fluidly connected to the first heat exchanger and the second heat exchanger, realizing the refrigerant cycle; a water collection tank that is disposed just under the first heat exchanger, wherein the water condensing on the first heat exchanger is collected, and a water softening unit that enables the water taken from the mains to be softened so as to be used in the washing step, characterized by a sump that is connected to the water collection tank and the water softening unit; a pump that is disposed between the water collection tank and the water softening unit, and a control unit that enables the water in the water collection tank to be transferred to the sump and/or the water stored in the sump to the water softening unit by means of the pump.
 2. A dishwasher as in claim 1, characterized by the sump that is disposed in the vicinity of the water softening unit.
 3. A dishwasher as in claim 1, characterized by a level sensor that measures the level of the water accumulated in the sump and the control unit that operates the pump, thus providing the intake of the water from the sump into the water softening unit if the value received from the level sensor is above a water level value predetermined by the producer.
 4. A dishwasher as in claim 2, characterized by the control unit that enables the water to be delivered to the water softening unit to be taken from the mains if the water level received from the level sensor is below the water level value predetermined by the producer.
 5. A dishwasher as in claim 2, characterized by the control unit that operates the heat pump independently from the washing and drying needs, enabling the amount of water accumulated in the sump to be increased if the water level received from the level sensor is below the water level predetermined by the producer.
 6. A dishwasher as in claim 1, characterized by a heater disposed around the sump and that provides the heating of the water stored in the sump. 